1. Field of the Invention
The invention concerns a network for packet-oriented data traffic wherein several nodes are connected by means of lines. The invention also concerns a node for such a network and a process for operating the same.
2. Description of the Background Art
The connection-oriented traffic of data with high data rate is gaining increasing importance. So-called ATM networks (ATM=Asynchronous Transfer Mode), for example, are currently being developed for local data traffic.
An ATM network is known from U.S. Pat. No. 5,475,682, wherein each node has a transfer function (switch). That is, the ATM cells that meet at a node of the network line are divided according to their corresponding destination into different output wait lines of respective network lines and then transmitted. The problem consists in that single or multiple nodes are overloaded when a high demand is placed on the network. In the known systems, therefore, it is provided that such overload situations are signalized to the nodes lying upstream by means of so-called backpressure signals. The data packets determined for the signalizing node are stored in a wait line in the upstream-lying node. If the wait line is full, then the data packets are still transferred to the node lying downstream. There, in the case of an overload, the packets with the longest bursts are pushed out of the memory and are lost. In this process, it should be avoided that a node can block all of the advancing ones.
The basic challenge with this known network structure is presented by the need to provide a minimum packet delay. For real-time applications, namely, it is unavoidable that the transfer takes place within an individually set time. It can also be important to determine within which variation the pregiven time limit can be kept. In the known networks, the transfer time (namely, if a greater amount of nodes must be traversed during the transfer of data) is relatively high and can also vary greatly.